Too much RAM after load scene textures in high resolution
So my solution to complete this project was:


I prepared same lowres textures in the different directory for example:
D:\MyProject\MyTextures for highres and D:\MyProject\MyTexturesLow for lowres
I used simple script for change name folder from MyTextures to MyTexturesLow and opposite
I renamed textures folder with script before open scene and switch back before render


It is only solution which save my project :) You can rename folder without script of course.